1. Field of the Invention
The present invention relates in general to water cooling type cooling systems for internal combustion engines, and more particularly, to an arrangement of the cooling system, which suits with a transversely mounted internal combustion engine.
2. Description of the Prior Art
In order to clarify the task of the present invention, one conventional arrangement of water cooling type cooling system for a transversely mounted internal combustion engine (which will be referred to as transverse engine hereinafter) will be outlined with reference to FIG. 14 of the accompanying drawings. The conventional arrangement is disclosed in Japanese Utility Model First Provisional Publication No. 62-69026.
As is shown in FIG. 14, the arrangement is applied to a V-type internal combustion engine which has a pair of banks angled, each bank having three aligned engine cylinders.
Cooling water pumped out by a water pump 1 is introduced into a water jacket of each bank from one longitudinal end of the bank. After cooling the engine cylinders of each bank, the cooling water is discharged from the water jacket from the other longitudinal end of the bank. When, due to a warm up condition of the engine, a thermostat 2 closes an outlet hose 4b for a radiator 3 while opening a bypass passage 5, the cooling water from the water jackets of both banks is forced to flow through the bypass passage 5 and a suction passage 6 and return to the water pump 1 in a manner as is indicated by shorter arrows. While, when, upon completion of the engine warm up, the thermostat 2 opens the radiator outlet hose 4b while closing the bypass passage 5, the cooling water from the water jackets is forced to flow through a radiator inlet hose 4a, the radiator 3, the radiator outlet hose 4b and the suction passage 6 and return to the water pump 1 in a manner as is indicated by the longer arrows.
Designated by "Va" and "Vb" are valves which are installed in their associated passages. Thus, when the valves "Va" and "Vb" are opened, the cooling water flows in a manner as is indicated by the dotted line arrows.
The water outlet opening of one bank to which the radiator inlet hose 4a is connected is designated by "WO", and the water inlet opening of the thermostat 2 to which the radiator outlet passage 4b is connected is designated by "WI" in the drawing.
However, the above-mentioned arrangement of cooling system becomes to have a drawback particularly when it is applied to a transverse engine.
That is, because the water outlet opening "WO" of the water jackets is located near the water inlet opening "WI" of the thermostat 2, at least one (viz., the inlet hose 4a in the illustrated example) of the inlet and outlet hoses 4a and 4b for the radiator 3 is complicatedly curved. In fact, the inlet hose 4a leading from the water outlet opening "WO" extends in one direction (viz., rightward in FIG. 14) and turns back to extend in the other direction (viz., leftward) and then turns toward the radiator 3 for connection with the same. These turnings of the inlet hose 4a however cause not a very lengthy structure of the hose 4a but also a tangled and jammed arrangement of the hoses 4a and 4b.
If the thermostat 2 is positioned at the end where the water pump 1 is arranged, the abovementioned drawback may be eliminated. That is, in this case, the inlet hose 4a and the outlet hose 4b for the radiator 3 are allowed to extend from the longitudinally opposed ends of the engine toward the radiator 3 without making undesired tangled portions thereof. However, usually, the transverse engine has near the water pump 1 no space for mounting such thermostat 5 because when the engine is transversely mounted in an engine room a vehicle, a bulky suspension device is positioned just above the water pump 1.